The study of complex systems has had an increasing interest over the last few decades. Market failures, International relations, and the quest to understand consciousness are some of the motives. The great advantage this field has is the massively broad scope. From understanding ecosystems to biological emergence to economics and war.

First, it might help to understand what exactly is a complex system. Some of the features that make up a complex system are –

1. Unpredictability

2. Large events

3. Robustness

4. Emergence

5. Novelty.

I’d go more into the details of each of these later on. From the last, evolutionary adaptation leads to fascinating creatures. The little neurons firing in your brain produce consciousness, an emergent phenomena. The same is true for ‘wetness’ – a property that emerges out of molecules combining to form water. An emergent property would be something that’s absent in the parts – neurons aren’t conscious and a single water molecule isn’t wet.

Robustness is even more common – a loss of one species wouldn’t destroy the the ecosystem; small strikes wouldn’t ruin an organization, neither would common failures destroy a market so easily – A complex system can withstand damage. Complex systems can produce really large events – war because of rising political upheaval; a global recession because market failures have reached a tipping point etc..

The more important feature is Unpredictability – these systems don’t keep doing the same thing periodically. Neither is their behavior totally chaotic. They border in-between.